SCAFFOLD StudyGore PTFE mesh-covered stent

preclinical and clinical data so far

Peter A. Schneider, MD

Kaiser Foundation Hospital

Honolulu, Hawaii

Disclosure

Peter A. Schneider

.................................................................................

I have the following potential conflicts of interest to report:

Scientific Advisory Board (non-paid):

Cardinal, Abbott, Medtronic, BSCI

Royalty (modest): Cook

Co-founder and Chief Medical Officer: Intact, Cagent

Enter patients into studies: NIH, Bard, Gore, Medtronic, BSI,

Silk Road (no financial relationship).

VIVA Board member (nonprofit)

Selected slides are courtesy of Claudio Schonholtz

CBAS

Coating

Gore Carotid Stent (GCS)

Stent

Frame

Stent

Lattice+

Investigational Device. Limited by US Law to Investigational Use only.

Gore PTFE mesh-covered stentDesign goals

• Flexibility/conformability

– Improved device navigation

– Open cell stent design enables device to conform to difficult anatomy

• High scaffolding potential

– Closed cell lattice to reduce stroke risk

• Minimize thrombus formation

– CBAS® Heparin Surface

Amazing array of configurations and morphologies

What About the Stent?

ScaffoldingLesion containmentConformabilityFatigue resistanceEase of re-crossingVisibilityLow profile

More Plaque Prolapse with Open Cell Stents

Plaque prolapse between stent struts

deDonato et al. Eur J Vasc Endovasc Surg 2013;45:479

Plaque Prolapse

Open Cell Closed Cell

61.5% 17.6%

Wholey J Endovasc Ther 2009;16:178

Schnaudigel et al. Stroke 2008;39:911

Closed Open

Closed cell (n=48)

Open cell(n=48)

P value

27.3% 51.1% 0.020

Park et al. J Neurosurg 2013;119:

More DW-MRI Lesions

with Open Cell Stents

Prospective RCT: MRI Hits

Closed versus Open Cell Stents

Delayed Neurologic Events (>24 Hours) with CAS

Bosiers et al. Eur J Vasc Endovasc Surg 2007;33:135

2/3 of neuro

events were

delayed (1-30d)

0-24 hours 1-30d % of strokes that occurred after 24 hours

29 events 19 events 40%

Hill et al. Circulation 2012;126:3054

CREST-Timing of Stroke After Carotid Stenting

GCS pore size <20% the area of WALLSTENT cell size

• Canine artery model

• Biologically acceptable tissue response– All sidebranches and

devices patent through 56 days

– Full device endothelialization at 30 days

– Comparatively less medial compression

GORE Stent

Carotid

WALLSTENT

SCAFFOLD: Gore Carotid Stent

Preclinical Studies

Carotid Stent Delivery System

Attributes•Single handed delivery

•5Fr Introducer Sheath Compatible (White Tip)

•6Fr Introducer Sheath Compatible (Gray Tip)

•Hypotube Design

– Allows for complete closure of hemostatic valve

•135 cm Working Length

•30 cm Rx

Hypotube(2.4 Fr)

Handle

Hub

Stent/Sheath(5Fr or 6Fr)

RO Markers

Gore Carotid Stent

SCAFFOLD StudyDesign-Prospective study comparing the GORE®

Carotid Stent to a performance goal developed from carotid endarterectomy outcomes.

50 sites, 312 subjects.

Co-PIs-Peter Schneider and Bill Gray

Objective-Evaluate safety and efficacy of GORE®

Carotid Stent in patients at increased risk for adverse events from carotid endarterectomy.

Primary endpoint-Death, stroke, or myocardial infarction through 30 days plus ipsilateralstroke between 31 days and 1 year.

Investigational Device.

Limited by United States Law to Investigational Use only. Not available in US. Not approved by FDA.

SCAFFOLD Study• Patient Population:

– >18 years of age

– De novo atherosclerotic or post-endarterectomy restenotic lesions in the CCA or ICA

– ≥50% (by angiography) stenosis if symptomatic, or

– ≥80% (by angiography) stenosis if asymptomatic

– High risk for CEA

• Design: – Stage 1: review 6 month data from first 100 patients

– Stage 2: contingent on Stage 1 review & approval to proceed

– Primary Endpoint: 1-Year Major Adverse Events – 30-day death/stroke/MI + ipsilateral stroke to 1 year

• Enrollment (approved):– Sites: 50 in US

– Subjects: 312

– FIM: August 6, 2013

• Status: IDE Approved December 15, 2012

SCAFFOLD Status

312/312 patients enrolled

30-day data to be presented at Charing Cross 2017

Gore Mesh-Covered Carotid Stent

Cases from the SCAFFOLD Trial

Courtesy: C. Schonholtz

Courtesy of

C. Metzger

Courtesy of R. Dave

SCAFFOLD Patient Selection: STAGE 1

100 patients enrolled and reviewed by FDA

Potential inclusion/exclusion criteria violations

Stenosis location or severity (inclusion)Severely tortuous anatomy (exclusion)Severe lesion calcification (exclusion)

Highest Risk Anatomies for CAS

1. Type III Arch

2. Vessel tortuosity

3. Heavy calcification

4. Lesion related thrombus

1. Vessel tortuosity

2. Severe arch disease

3. Angulated ICA

4. Circumferential calcification

McDonald et al, Stroke 2009 White et al, Cath Card Int 2013

SCAFFOLD Patient Selection:

STAGE 2Additional 212 patients enrolled, subject to a

screening committee for eligibility

• Physicians from different disciplines

• 1 NS, 1 IC, 1 IR, 1 VS

• Review CTA or angiograms for

inclusion/exclusion criteria based on

protocol

• 2 review each case; if no consensus, 3rd

physician included

• Patients either accepted or rejected for

enrollment in SCAFFOLD

Patients Rejected by

Screening Committee

1 Severe lesion calcification2 Severely tortuous anatomy 3 ≥50% stenosis of proximal CCA

• SCAFFOLD Trial studied next development in carotid stent design. Release Q2 2017.

– Open cell stent frame, PTFE mesh, heparin coating

• Make the first 30 days safer.

– Smaller cell size=less plaque prolapse, fewer delayed events

– Case selection for carotid stenting is key to good clinical results and evaluating device performance

• Future stent design likely to include some type of coverage.

Mesh-Covered Stent and SCAFFOLD Trial

Conclusion

GORE® Carotid Stent Clinical Study for

the treatment of carotid Artery stenosis

in patients at increased risk For adverse

events From carOtid enDarterectomy

The Gore SCAFFOLD Clinical Study

CAUTION: Investigational Device. Limited by United States Law to Investigational Use only.

SCAFFOLD StudyGore PTFE mesh-covered stent

preclinical and clinical data so far

Peter A. Schneider, MD

Kaiser Foundation Hospital

Honolulu, Hawaii